Hi,
There are planes clad in rainbow colors over the sea near Ukraine. Is this normal ? What 's going on here ?
What exactly is going on here but I can’t understand.
Kind regards,
Thank you.
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Hi,
The effect that you are seeing in these RGB visualisations is related to the way Sentinel-2’s sensor works. Indeed, the 13-band multi-spectral detector on board the satellite captures reflected sunlight (from the Earth) at different wavelengths with a slight temporal delay (which can reach up to 2.6 seconds).
Since airplanes are fast moving objects, they will move between the acquisitions of the different bands. You can see this with an example GIF looping through Sentinel-2 bands (curtesy of kosmi64833127 on Twitter):
If you combine three bands together for an RGB visualisation, like your example, you will see the contribution of each channel (red, green and blue) in slightly different locations. Furthermore, the direction of the offset depends on the airplane heading.
If your curiosity is raised, you can dig deeper into the subject and read the paper that determines velocity from band offsets.
Lastly, you can also observe this effect with other fast moving objects: trains, trucks…
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Sorry, I don’t want to hide my facial expression… Wow incredible. Thank you for the keywords you provided. Even though I stayed on for 15 minutes, it guided me to many places. Good work. Kind regards.